#include"iostream"

using namespace std;

const int N = 100010;

int head, e[N], ne[N], idx;

void init()
{
	idx = 0;
	head = -1;
}

void add_to_head(int x)
{
	e[idx] = x, ne[idx] = head, head = idx++;
}

void add(int k, int x)
{
	e[idx] = x, ne[idx] = ne[k], ne[k] = idx++;
}

void remove(int k)
{
	ne[k] = ne[ne[k]];
}
int main()
{
	int m;
	cin >> m;
	
	init();
	
	while(m--)
	{
		int k, x;
		char op;
		cin >> op;
		if(op == 'H')
		{
			cin >> x;
			add_to_head(x);
		}
		else if(op == 'D')
		{
			cin >> k;
			if(!k) head = ne[head];
			else remove(k - 1);
		}
		else
		{
			cin >> k >> x;
			add(k - 1, x);
		}
	}
	for(int i = head; i != -1; i = ne[i]) cout << e[i] << ' ';
	cout << endl;
	
	return 0;
}

